Characterization of Key Vehicle Parameters Affecting Dynamic Rollover Propensity Using Simulation and 1/10th Model Testing

Rollover propensity is an important safety issue which should be considered early in the design of a vehicle. Although there is a trend toward higher-tech solutions to mitigate rollover risk, we feel that a vehicle designer should also be fully aware of the impact many of the vehicle's design parameters have on rollover propensity. Such awareness is essential to making appropriate engineering tradeoffs throughout the vehicle development process.

In this paper, we present a study performed to gain a better understanding of the factors affecting the roll tendency of a vehicle. The equations of motion for a vehicle ignoring suspension effects and tire deflections are developed to gain an understanding of the physics involved and to preliminarily identify factors using a generic Matlab™ code. Further and more complete analysis was then completed using ADAMS™ Car. ADAMS™ Insight was used to vary few dynamic parameters for the vehicle executing a Fishhook maneuver, and a statistical analysis was performed on the resulting data using Minitab™.

Experimentation was conducted on 1/10^th model of Traxxas remote control car to see if the same conclusions reached in simulation could be obtained with scale model testing. For combinations of the varying dynamic factors in a fractional factorial experiment, the roll angle is measured using a sensor and statistical analysis is performed on the resulting data using Minitab™. The simulation and scale model test results are compared to conclude the relative impact of the factors on roll tendency. This knowledge can help automotive engineers better understand the impact of design decisions involving the parameters under study.